This invention relates generally to a liquid supplying nozzle and more particularly to a liquid supplying nozzle which is so adapted that it can supply a liquid of a specific kind into only a specific liquid filling inlet and cannot supply the liquid into a liquid filling inlet for other kinds of liquids.
Heretofore, as a gasoline (petrol) for motor vehicle use, lead containing or adding gasoline, prepared by adding tetraethyllead to gasoline to increase the octane number thereof, has been used. However, in the exhaust gas of an engine which uses this lead containing gasoline, lead compounds are present and become one cause of atmospheric pollution.
Lately, environmental impairment, particularly atmospheric pollution is becoming a serious problem, and there is a trend toward the obligatory use of gasoline not containing lead compounds, that is, leadless gasoline, instead of lead containing gasoline.
However, in the period of transition during which the vehicles using lead containing gasoline are totally replaced by vehicles using leadless gasoline, these two kinds of vehicles will coexist. Accordingly, during this period, it is necessary to prevent the supplying of lead containing gasoline into the fuel tanks of vehicles using leadless gasoline in order to minimize atmospheric pollution.
One measure which would appear to be suitable for solving this problem is simply to make the diameters of the fuel tank inlets and refueling nozzles for leadless gasoline smaller than those for lead containing gasoline thereby to prevent nozzles for lead containing gasoline being inserted into the fuel tank inlets for leadless gasoline. A conventional refueling nozzle, however, is adapted to discharge gasoline when the operating lever is squeezed irrespectively of whether or not the nozzle end is in a state of insertion in a fuel tank inlet. For this reason, it is quite possible to foresee the case where an operator intentionally squeezes the operating lever of a nozzle for lead containing gasoline with the nozzle tip pressed against the inlet of a fuel tank for leadless gasoline thereby to forcibly and deliberately fill the tank with lead containing gasoline. It can be foreseen that such a procedure will be apt to occur particularly in cases where self-service is practiced in a fuel filling station.
Accordingly, it is desirable that a refueling nozzle for lead containing gasoline be so adapted that it is not merely prevented from being inserted into a fuel tank inlet for leadless gasoline but is prevented also from supplying gasoline therethrough.
Furthermore, there is also a need for a device which, in addition to differentiating between leadless gasoline and lead containing gasoline as described above, is capable of preventing erroneous refueling with different kinds of liquids such as, for example, gasoline and light oil.